Multivariate chemometrical classification and assessment of Lake Tuendae: A Mojave desert aquatic environment housing the endangered Mojave Tui Chub

Abstract

Lake Tuendae is a shallow, alkaline, artificially constructed Mojave Desert aquatic environment housing the endangered Mojave Tui Chub ( Gila bicolar mohavensis). Detailed physiological response studies have been reported on the Mojave Tui Chub but few on the physico-chemical state of Lake Tuendae, one of four key Mojave Desert habitats for this species. Two sampling campaigns (spring 2004 and 2005) were conducted with correlation analysis, cluster analysis (CA) and principal component analysis (PCA) of physico-chemical water column and surface sediment quality parameters performed. CA proved useful in displaying parameter similarity for initial interpretation. PCA proved to be a more reliable display model and permitted the reduction of 14 parameters for the water column to four principal components accounting for 71% of the total variability. For surface sediments, four principal components accounted for 81% of the total variability. This work highlights the successful use of chemometric multivariate techniques in helping elucidate the physico-chemical make-up of shallow desert aquatic environments, and instructive for investigators assessing the health of aquatic species in such habitats.